SOLUTION: A is a reflexive angle whose sin is -5/13. Find:
1. sin (2A)
2. cos (2A)
3. sin (4A
4. cos (4A)
Show your calculations.
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-> SOLUTION: A is a reflexive angle whose sin is -5/13. Find:
1. sin (2A)
2. cos (2A)
3. sin (4A
4. cos (4A)
Show your calculations.
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Question 1105377: A is a reflexive angle whose sin is -5/13. Find:
1. sin (2A)
2. cos (2A)
3. sin (4A
4. cos (4A)
Show your calculations. Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! A is a reflexive angle whose sin is -5/13.
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The terminal point is in Q4 at (12,-5)
x = 12
y = -5
r = 13
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Find:
1. sin (2A)
sin(2A) = 2sin(A)*cos(A)
cos(a) = x/r = 12/13
sin(2A) = 2(-5/13)*(13/13) = -10/169
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2. cos (2A)
cos(2A) = sqrt(1 - sin^2(2A))
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3. sin (4A)
Same as #1
4. cos (4A)
Same as #2
